What is a warm transfer?

A cold transfer simply redirects the call. The person who picks up knows nothing, so the caller repeats everything, which erases most of the benefit of having answered quickly in the first place.

A warm transfer passes a summary, the transcript, and any captured details to the human before or as the call connects. Done properly the handover is invisible: the human opens with knowledge of what has already been said.

Deciding when to transfer is a policy question, not a technical one. Most deployments escalate on explicit request, detected frustration, anything safety-related, and anything the agent cannot ground in its knowledge. The exact list should be written down before launch.